The two links above are reliable. I use NARVA lamps sourced through Stern, and CIBIE lamp housings as first choice. You simply cannot go wrong using products and advice from Mr. Stern. He is an easy man to work with and I seriously doubt any aftermarket supplier such as him has a better reputation based on the many vehicle-enthusiast boards where his name/site pop up.
Start by downloading/printing his diagrams. After looking at your vehicle, make your own as well. You'll want things such as fuse holders located such that you can easily check them, but are mounted so as to be out of the way. You want to know lengths before cuts, number of cuts, etc. Find the place to attach the relays to sheetmetal, and later have a way of tagging each (plus fuses) as high or low beam.
Choice in wiring products should be ANCOR in all cases, IMO. I would expect to spend $300-400 (and more, as below) for all parts/supplies/tools. I don't want to ever have to re-build or repair this. Buy highest quality crimpers and strippers if you don't have them (not Home Depot, but an electrical supply house or Snap-On dealer, etc). You may wish to purchase an ANCOR catalog as I have done to see the full-range of possible supply (and in below links).
You'll want to make measurements from the battery to the headlamps via existing wiring harnesses as near as possible, plus a bit more. Run some twine and attach lightly. The "ideal", IMO, is to construct harnesses similar to the way the factory does it. Although unlikely, you'd want to be able to remove this wiring as its' own bundle.
I start at the headlamp location (after they are removed) plus a bit of slack after stripping (very clean, no nicks or breaks; practice on scrap), and work them along existing pathways, or pathways protected from road debris, engine fan, belts, etc. I temporarily tie them in place with some light bare wire, and mark or note the places I will (preferably) use cushioned Adel Clamps
with stainless self-tapping sheetmetal screws (for which I still point-mark and pilot-drill). I also buy several types of ss nylon-coated cable ties
; both the type that is attachable via fastener to the metal, or simply pull tight. I expect to "bind" the cabling every 6", and support it every 6-8". Never taut, always a bit loosely.
As this is heavy I may have to do new supports for existing wiring with the above, so different sizes may be needed for solo running or conjoint runs.
After both headlamp sides are measured, routed and cut I remove them and cover with plastic split-loom conduit and proceed to attach along the chosen routing. (This is always a good stopping point for the day, IMO, as one can be under the vehicle and back out on one's feet multiple times depending on the vehicle, etc. I may have installed and removed the harnesses a half-dozen times. I may also slightly move other ones around so as to accommodate this work).
I use ANCOR adhesive-filled "shrink" terminations and connectors. No exceptions. With 12-2 or 12-3 multi-strand ANCOR cabling this makes for USCG-approved installations. No soldering (as vibration loosens soldered connexions over time). And no problems years down the road. Buy a few more than you need.
One will need waterproof fuses, so ANCOR again, with holders (and spares).
The last one I did was for my USMC pilot son on his Jeep. After six years and being stationed directly
on the Atlantic once, the Gulf Coast twice and the West Coast once and 70k miles there have been no problems. As I requested he purchased one extra set of lamps (always replaced in pairs) and they have been since installed. We call them Alien Landing Lights
as they are more powerful than is quite legal . . but because I use Mr. Sterns Headlamp Adjustment instructions carefully, we have also never been "flashed" by oncoming traffic while on low-beam. (And, with a big load on board, we also know how many turns of the adjusting screw to re-aim).
I also did the Big Three Upgrade
to reduce system strain should he add a two-way transceiver or faincy stereo. I simply used HD marine batt cabling pre-made in various lengths (too long is easier to deal with than too short), plus new batt cables with mil-spec clamps from this firm
and a big marine fuse & holder.
This is also a good time to relay-run the factory electric "city horn[s]" and add a pair of HELLA Supertones
behind or on the grille.
The single caveat to doing this is the risk of damaging old, brittle factory wiring. Heat, miles and age take their toll. Time spent planning is more important than the actual work. Strain on existing harnesses is a no-no as is routing near high heat sources. The more time spent removing components (grille, etc) the better. Even on the cars/trucks I've done -- nearly new compared to these antiques (10+ years) -- I remove as much as possible.
And expect to get dirty. Use safety glasses as dirt will rain on you at moments you are concentrating from underneath (vehicle dependent).
This is a job that, done well, takes a LOT more time than it appears it should. Better-than-factory is never so easy as it first appears. What looks like two hours is for me a two day job full-time, minimum. I'm slow, and don't care a bit as headlamps, horns and primary charge circuit upgrades are a reliability/longevity upgrade.
(PM me after your homework if needed; we can add it to this thread once all is sorted)